Plaster lath.



J. P. SEXTON.

PLASTER LATH.

APPLICATION FlLED NOV.6. I916.

1 ,298,4;1 1 Patented Mar. 25, 1919;

IM /72W m x/ 0, 1 i

TED STATE PATENT @FETGE.

JAMES P. SEXTON, OF LOS ANGELES, CALIFORNIA, ASSIGNOR T0 BUTTONLATH MANUFACTURING COMPANY, 013 LOS ANGELES, CALIFORNIA, A CORPORATION OF CALIFORNIA.

PLASTER LATH.

Specification of Letters Patent.

The improvements herein concerned relate preferably to that form of plaster lath wherein protrusions, buttons or the like, are situated in longitudinal or elongated grooves in the face of the plaster lath, although not necessarily limited to such forms as will hereinafter appear.

I explain in detail a preferred form of plaster lath herein concerned in the following specification, reference being had to the accompanying drawings in which: Figure l is a face view said plaster lath; Fig. 2 is a transverse section thereof, and Fig. 3 is a longitudinal section thereof.

The plaster lath comprises a form or facing sheet 10 of paper or other suitable material, waterproofed or otherwise prepared or treated as desired; a cementitious base or body 11 of plaster, mortar or the like, and a back sheet 12 of paper or the like. The facing sheet 10 is corrugated so as to form longitudinal grooves 10*, in the manner illustrated, and at suitable points in the grooves I provide perforations 14 through which the plaster or cementitious material of the face may protrude to form the buttons 13. The buttons 13 do not project above thesurface of the upper edges of the facing sheet 10, and may have their outer ends either flush or somewhat below this surface, so as to facilitate packing and transportation.

These buttons 13 may be any kind of protrusion of the cementitious body, or may. be in the particular wedge shape herein shown, larger at their outer ends than at their inner ends; so that they form keys around which the applied or superimposed plaster 15 may set. The key shape of the buttons not only keys the applied plaster to the plaster lath but also acts to hold the facshowing a preferred form ofing sheet 10 upon the body 11. The apertures 14 may be spaced in the facing sheet 10 as desired, preferably being placed at the bottoms of the grooves 10 and spaced in general staggered relation, as is clearly shown in the drawings. When the applied plaster is put upon the lath, after the lath has been secured to the walls in any suitable manner, the applied plaster flows into the longitudinal or elongated grooves 10 and flows around the flared buttons 13, engaging around and under the edges of the buttons to form a substantial and lasting bond. The applied plaster 15 easily enters the groove 10, by reason of the open character of the groove; and, because the grooves are elon- Patented Mar. 25, 1919.

gated, it is practically impossible to trap air under the plaster being applied and to thus prevent good application of the plaster.

The form of plaster lath thus described is made by depositing the corrugated facing sheet face down upon a suitable surface, preferably a smooth flat surface, applying a uniform layer of plaster over the surface and applying the back sheet 12, the plaster or other cementitious material running through, or being forced through the openings 14 to. form the protrusions 13. \Vhen the consistency of the cementitious substance is properly regulated, it will flow through the openings and contact with the flat surface and expand when it contacts with the surface to form the flared or keyshaped buttons.

I show the openings 14 and the protrusions 13 more or less rectangular in formation and confined between expanding flanges 20. These flanges 20 are in the nature of lips forced out of the facing sheet 10 to form the openings 14 and bent to a transverse or forwardly projecting position. And when the cementitious material flows or is forced through the openings 14, the parts 20 are spread apart at their outer ends so that the final shape of the button 13 is flaring. Preferably, the parts 20 are of such length that they do not quite reach to the upper surface of the facing sheet; and as a' result the cementitious substance may flow over the edge of these members 20, as shown at 21, to form an edge which aids in keying the applied plaster 15 to the lath. Also the members 20 are not quite as wide as the grooves 10, and the plaster which forms the lowing claims.

buttons or protrusions may flow past the lateral sides or corners of members 20 to form'the small protrusions as is indicated at 22 at certain places in Fig. 1. These extra protrusions aidin keying the applied plaster to the plaster lath.

The foregoin described form of plaster lath is typical of otherswhich may be made, embodying-the same fundamentals and rinciples of design and construction. I t erefore do not limit myself to the exact details shown and'descri'bed herein, as these details maybe varied within the scope of the fol- Having described a preferred form of my invention, 1 claim: Y

1. A plaster lath, comprising a cementitious body and a perforated facing sheet,

said facing sheet being corrugated to-present longitudinal grooves, the perforations being spaced in the grooves, and the cementitious body projecting through the perforations to form flaring buttons in the grooves, and portions of the facing sheet standing out as lips across the grooves at opposite sides of the buttons, so that the flaring buttons are. substantially completely confined by the groove walls and the llps.

2. A plaster lath, comprising a cementitious body and a perforated facing sheet,

said facing sheet being corrugatedto present longitudinal rooves, and the cementr 'tiousbod projectingthrough the perforations to orm protrusions, and portions of the facing sheet standing out as lips-across the grooves on. the opposite side surfaces of a protrusion and delimiting, the protrusion lengthwise of the groove, so that the protrusions are substantially completely confined by the groove walls and the lips.

3. A plaster lath, comprising a cementitious body and a perforated facing sheet,

said facing sheet being corrugated to present longitudinal ooves, and the cementitious body projecting through the perforations to form protrusions and portions of the facing sheet standing out as lips across the grooves at opposite sides of the protrusions, the lips extending not quite to the top of the grooves and the protrusions extending substantially flush with the top of the grooves so that the cementitious pro-' somewhat overhang the end a protrusion and delimiting the protrusion lengthwise of the groove, and'the lips ending somewhat short of the sides of thegrooves so that the cementitious protrusion may overhang the edges of the lips next the groove wall substantially as described.

In witness that I claim the foregoing .I have hereunto subscribed my name this 30th day of October 1916.

Witnesses: I

JAMns T. BARKELEW, 1 Enwoon H. BanKELnw. I

J. P. SEXTON. I 

